/Engine/Source/Runtime/MovieScene/Public/EntitySystem/MovieSceneEntityManager.h
Add the specified components to an entity. Existing components will remain unchanged. New component values will be default-initialized.
void AddComponents ( [FMovieSceneEntityID](API\Runtime\MovieScene\EntitySystem\FMovieSceneEntityID) EntityID, const [FComponentMask](API\Runtime\MovieScene\EntitySystem\FComponentMask) & EntityComponentMask, [EEntityRecursion](API\Runtime\MovieScene\EntitySystem\UE__MovieScene__EEntityRecursion) Recursion )